US Patent 7633484 Display unit

A display unit includes a display panel having a display screen on which images are displayed, and (b) a touch panel covering the display screen therewith and detecting a touch thereto made by a user. The touch panel detects the touch in accordance with touch-panel drive signals input thereto. The display panel displays images in accordance with display-drive signals input thereto. The touch panel is switched between a first condition in which the touch-panel drive signals are input into the touch panel and a second condition in which the touch panel is electrically open.